With the extended use of marine devices that use marine type propellers such as are mounted on inboard motors, outboard motors, inboard-outboard motors, or similar water propulsion devices, a problem that is becoming more prevalent is the unauthorized removal and theft of expensive marine type propellers.
Accordingly, the provision of a satisfactory lock is very desirable. However, there are several major problems. One is that such a lock could become incompatible when applied to a high speed marine propeller if it causes any unbalance to the precision balanced assembly and may thereby reduce the efficiency of the propulsion device and possibly shorten its life expectancy. Secondly, the lock is subject to contamination by water, solids and the like, and also tends to corrode.
Accordingly, among the objects of the invention are to provide a satisfactory marine type propeller lock which will effectively prevent unauthorized removal or substitution of any propeller while the boat is operational in the water, stored on land, or being transported by land; which is effective without loss of engine efficiency; which is adaptable to inboard motors, outboard motors, inboard-outboard motors and similar water propulsion devices; which is adaptable to various propeller fastening means such as nut and cotter pin and lock tab washers, nut and locking pin, nut and keyed tapered shaft, self-locking nuts and the like; which will prevent willful, malicious or accidental tampering with the propeller that might result in propeller loss under power; which can be utilized on the output shaft of the power source even when the propeller is removed to prevent damage to the propeller and still protecting the output shaft end while the boat is being handled on shore or on land; which is self-cleaning so that the tendency for corrosion, contamination with solids and the like is minimized; and which is self-lubricating.